In posting the latest travel alert for the Cayman Islands, Antigua and Barbuda, and the Turks and Caicos Islands, the CDC said it is “working with other public health officials to monitor for ongoing Zika virus‎ transmission.”

“Travelers to areas with cases of Zika virus infection are at risk of being infected with the Zika virus,” it said. “Mosquitoes that spread Zika are aggressive daytime biters. They also bite at night. There is no vaccine or medicine for Zika virus. The best way to avoid Zika virus infection is to prevent mosquito bites.”

The CDC said some travelers to areas with Zika will become infected while traveling, but will not become sick until they return home, adding that they might not have any symptoms.

To help stop the spread of Zika, the CDC urged travelers to use insect repellent for three weeks after travel to prevent mosquito bites. It said some people who are infected do not have any symptoms.

The CDC said people who do have symptoms have reported fever, rash, joint pain and red eyes. It said the sickness is usually mild with symptoms that last from several days to a week.

Severe disease requiring hospitalization is uncommon, and the number of deaths is low, said the CDC, adding that travelers to areas with Zika should monitor for symptoms or sickness upon return.

“If they become sick, they should tell their healthcare professional when and where they have traveled,” said the CDC, disclosing that it has received reports of Zika virus being spread by sexual contact with sick returning travelers.

Until more is known, the CDC said it continues to recommend that pregnant women and women trying to become pregnant take a number of precautions, such as not traveling to any area with Zika.

If they must travel to or live in one of these areas, the CDC urged them to talk to their healthcare provider first and strictly follow the outlined steps.

If pregnant women or their partner live in or travel to an area with Zika, the CDC recommended the use condoms or other barriers, “the right way, every time you have sex or do not have sex throughout the pregnancy.”

Meanwhile, the European Centre for Disease Prevention and Control (ECDPC) said that, since February 1, 2016, Zika virus infection and the related clusters of microcephaly cases and other neurological disorders have constituted a “public health emergency of international concern (PHEIC).”

Since 2015, and as of August 4, 2016, the ECEDPC noted that the World Health Organization (WHO) has reported 65 countries and territories with mosquito-borne transmission.

“There is now a scientific consensus that Zika virus is a cause of microcephaly and Guillain-Barré syndrome,” said the ECDPC, adding that, as of August 3, 2016, 14 countries or territories have reported microcephaly and other central nervous system (CNS) malformations potentially associated with Zika virus infection or suggestive of congenital infection.